Gear: Exercise equipment that's on the ball

What do you get when you mate old-school strength devices like push-up bars, ab wheels and vertical knee-raise, dip and pull-up stations with balls? Some of the most innovative, effective home fitness devices to come along in recent years.

SKLZ Core Push-Up Instability Strength Trainer: An 8-pound, skateboard-shaped aluminum platform has handles that you push up from while it is balanced on an inflatable 4-inch diameter ball.

Likes: Spectacularly challenging push-ups that force you to stabilize your entire body. With the slightest left-to-right imbalance, the platform rolls around on the ball like a sailboat on choppy seas. You must mobilize your core and entire body to stop the rocking. This is hard — and certainly effective. My normal consecutive push-up max is 65; on this I did 20. Other features: two hand positions: 24 inches apart on the handles, and a narrower 14-inch grip using cut-outs in the board itself. Drawings on the board show different workout positions. Blowing the ball up harder increases the difficulty. Most push-up bars seem unnecessary — but not this one.

Dislikes: With no fabric or rubber on the edges, it'll scratch a wood floor. But it's still plenty challenging on carpet, a rug or concrete.

Rock 360 Rolling Core Kinetics: Dual-handled, omni-directional abdominal roller, invented by former Detroit Lions and University of Missouri receiver Tommy Saunders, replaces the wheel of the age-old ab wheel with a ball.

Likes: An extremely effective, creative and fun way to blast your core. Resembling a double-handled ice cream scooper with a bowling ball where the ice cream would be, it makes the venerable ab wheel look and feel like a Model T. Sprawling forward, you smoothly flow over the floor in 360-degree motions, not just back and forth. Instantly moving every which way keeps your abs, glutes, spinal erectors and virtually every other muscle of your body frantically firing in multiple planes to keep you in balance. It also keeps you doing it far longer than you would with the old uni-directional wheel. Included is a foam knee pad and a highly motivating downloadable app that maps your workout pattern (currently available for Android phones, with iOS coming soon).

Likes: Fun, challenging, highly functional total-body workout. The routine builds good flexibility and range of motion, and is very convenient, since you use only one piece of equipment. The DVD and a printed workout guide include five workouts that use 140 exercises. A free downloadable Ugi interval timer app for the iPhone is available.

Dislikes: You can't do floor slams because the Ugi ball won't bounce. But it's fine for wall ball.

BodyCraft T3 Life Tree: Super-functional pull-up, leg-raise and dip station uses a 55-centimeter inflatable ball instead of a conventional back pad and adds stretch-cord attachments.

Likes: Great variety of whole-body exercises. Starting with the three aforementioned main exercises, you also get hanging leg-lifts (via elbow slings), an excellent back extension (lie face-down on top of the ball and raise legs by flexing glutes and spinal erectors) and an infinite number of push and pull stretch-cord exercises (via three different-thickness latex resistance cords that clip by carabiner to the frame's numerous high, middle and low attachment points). The fold-away dip handles are angled for different widths. The cords can be used for assisted pull-ups. The ball, moved to the floor, does double duty as a stability push-up and situp platform. Bottom brackets allow push-ups and reverse dips.

Dislikes: At 83 inches high, it needs to be 6 inches taller to keep my dangling feet from touching the floor (I'm 5 feet, 9 inches). It also needs a pump holder, so you won't lose it.